N UCL E AR E N E RG Y V S.

AL TE RN ATIV E E N E RG Y

CONTENTS

Abstract ....................................................................................................................................................................... 1

1. Introduction..................................................................................................................................................... 1

2. Nuclear Energy ............................................................................................................................................... 2

2.1 What is nuclear energy? ................................................................................................................... 2

2.2 Nuclear fission ...................................................................................................................................... 2

2.3 Nuclear fusion ....................................................................................................................................... 3

2.4 Advantages of nuclear energy ................................................................................................... 4

2.5 Disadvantages of nuclear energy ............................................................................................. 4

3. Alternative energy ........................................................................................................................................ 5

3.1 Solar energy ........................................................................................................................................... 5

3.2 Wind power ........................................................................................................................................... 5

3.3 Hydraulic energy ................................................................................................................................. 6

3.4 Biomass energy .................................................................................................................................... 6

3.5 Tidal energy ........................................................................................................................................... 7

3.6 Geothermal energy ............................................................................................................................. 7

Conclusions ................................................................................................................................................................ 8

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ABSTRACT

In this essay we will learn about what is and how works nuclear energy, what is the

difference between nuclear fusion and nuclear fission, its advantages and disadvantages

against other alternative energies and the different alternatives that we know and we can

use in order to change this kind of energy to a cheaper and/or less contaminant one.

1. INTRODUCTION

Energy is a natural resource that can be used in industries as from the application of

technology and other related resources. This concept can also be the capacity of move or

transform something.

Nonrenewable energy is the one that comes from exhaustible resources. However,

renewable energy is infinite.

Nowadays, society is being more concern about the environment protection, so a huge

boom of renewable energies is being produced. The use of them contributes to the end of

the use of another resources that contaminate and harm our natural environment and

consequently also our health.

The base of the use of the renewable energy is that they opt for an energy that uses

inexhaustible natural energy resources, like the solar energy. In the same way, looks for an

energy that can be regenerated in a natural way, so it does not damage the natural

environment.

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2. NUCLEAR ENERGY

2.1 WHAT IS NUCLEAR ENERGY?

The nuclear energy is an energy that is obtained from the manipulation of the internal

structure of the atoms. It can be obtained from two different reactions: the division of the

nucleus (nuclear fission) or the fusion of two of them (nuclear fusion). When one of these

reactions is produced, atoms experiment a slight loss of mass. This loss of mass is

converted to a huge amount of heat energy.

Usually, this energy is used in order to generate electric energy in nuclear plants but it can

be used in many other applications, such as medical, environmental or warlike

applications.

2.2 NUCLEAR FISSION

Nuclear fission is the name that we give to the nucleus division of an atom. The nucleus is

converted to some fragments with an almost equal to the half of the original mass plus two

or three neutrons.

This reaction can happen when a nucleus of an atom catch a neutron or it can be

spontaneous.

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A chain reaction is a process where one of the neutrons that has been released in the

nuclear fission produces another fission in, at least, one more nucleus. This nucleus

releases neutrons, therefore the process is repeated.

Although in every fission two or three neutrons are produced, not all of them are ready to

continue with the process.

2.3 NUCLEAR FUSION

Nuclear fusion is the name of the reaction when two light atoms (generally hydrogen and

its isotopes) are joined to created a heavier nucleus, producing a big amount of energy.

In order to get this reaction, the following requirements are needed:

Extremely high temperature to separate the electrons from the nucleus.

Confinement enough to make this high temperature stable for a minimum time.

Density enough to have the nucleus close to each other.

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2.4 ADVANTAGES OF NUCLEAR ENERGY

One of the advantages of nuclear energy is the relation between the amount of

combustible that is used and the energy that is produced.

Given that it is an alternative of fossil fuels, we can prevent global warming and it would

improve our quality of life and the quality of the air that we are breathing.

2.5 DISADVANTAGES OF NUCLEAR ENERGY

The principal disadvantage is that its security is dangerous and its use is on people

responsibility. Irresponsible decisions can cause accidents in nuclear plants however, it

can be used with a military purpose as the history says, the first time it was used with this

purpose was in II World War to attack Japan with two nuclear bombs.

One of the most important disadvantages is the generation of nuclear wastes and the

difficulty to manage them, given that a lot of years are needed by them to lose its

radioactivity and dangerousness.

Security drawbacks are incremented because of the international terrorism. Also the

proliferation of nuclear energy would force the use of plutonium as fuel.

Even security systems being so much advanced, nuclear fission reactions generate some

chain reactions and if the control systems fail can cause a radioactive explosion.

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3. ALTERNATIVE ENERGY

3.1 SOLAR ENERGY

We can distinguish two ways of the use of solar energy:

Thermal solar energy

Photovoltaic solar energy

The use of thermal solar energy consists on utilize heat energy obtained from solar

radiation to warm a fluid up that, depending on its temperature, is used to produce hot

water or even steam.

The use of photovoltaic solar energy is accomplished through the direct transformation of

solar energy to electricity via the photovoltaic effect. This transformation is achieved by

means of ‘solar cells’ that are made from semiconductor materials that generate electricity

when the solar radiation impacts on them.

3.2 WIND POWER

Wind energy systems use the kinetic energy that is contained in the wind in order to

produce electricity through turbines. There are two kinds of wind energy systems:

Wind farms, composed of some turbines, so as to sell electricity generated to the

network.

Isolated, in order to generate electricity in remote places for own consumption. It

is very common that these wind energy systems are in combination with

photovoltaic panels.

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The actual technologic development, so as an improved knowledge of the wind conditions

in every area, is enabling the creation of wind farms that are connected to the network in

numerous areas all over the world.

3.3 HYDRAULIC ENERGY

The use of the electricity that is produced from water’s jump is known as hydraulic energy.

The water moves a turbine whose rotation movement is transferred through an axle to an

electricity generator. This kind of energy is considered as renewable when the power is

smaller than 10MW.

There are two types of hydraulic plants:

Flowing water plants: those that get a part of the flowing water of a river and put it

through the plant in order to be turbinated and generate electricity. After this, the

flowing water goes again to the river.

Based on the dam plants: those that are placed at the base of the dams that are

made to hydraulic applications or to supply water to cities. They have the

advantage of store energy and it can be used whenever it is necessary.

3.4 BIOMASS ENERGY

Biomass is an energy resource based on the use of organic substances of vegetable or

animal origin, including the products or by-products from the transformation. Bio fuel is

considered a biomass and transport is its principal application.

The applications of biomass can be separated in two groups:

Industrial or domestic applications that work through the direct combustion of the

biomass.

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Applications related to new resources and new ways of transformation, such as

gasification and pyrolysis of the biomass.

3.5 TIDAL ENERGY

Seas and oceans are a huge solar collectors where energy from some kind of origin can be

generated, such as from wave, tidal and thermal gradients.

The energy released by seas and oceans, in the ascent and descent movements of the tides,

is used in the tidal plants, making the water to go through the hydraulic turbines.

Tidal energy is produced by wind and that makes it irregular. This has induced to build a

lot of types of machines to find the best one for its use.

Finally, to convert thermal ocean energy is to convert to useful energy the difference

between the temperature of the surface and the temperature of the water that is 100

metres deep. At least a difference of 20 degrees is necessary in order to take an advantage

of this. The advantages of this energy resource are related to a permanent and benign

thermal jump from a environmental point of view.

3.6 GEOTHERMAL ENERGY

Geothermal energy is the manifestation of the thermal energy accumulated in rocks or

water that are placed in the interior of the earth at a huge temperature.

To use it in special thermal conditions places, such as volcanic zones, a fluid is circulating

through them and transports the heat energy to the surface in a heat form.

The energy generated in a heat way is used to produce electricity or to get hot water and

heating.

The principal advantage of geothermal energy is that its impact on the environment is

minimum and has skills that make it compete with petrol. However its principal

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disadvantages is that it requires a high invest, there are not a lot of them and usually they

are placed in adverse areas.

CONCLUSIONS

For a conclusion, alternative energies are so much better than nuclear energy because

they are renewable, so the environment will not be damage and it is unlimited, and there

is not the possibility of it being dangerous as the nuclear energy is.

The big problems with alternative energies are that the fact that they are not useful all the

time because of their natural behavior and we can’t get the control of them, the only way is

studying places we can find to get them and use them in order to get the best functionality,

and sometimes the huge invest we have to get so as to make them work.